The neutron-lbaas-dashboard repo had legacy code that is not used in
the current version of the dashboard. This patch removes that code.
Note: This is modeled after Michael Johnson's patch to do the same
for octavia-dashboard: https://review.openstack.org/#/c/496961/
Change-Id: I20e6bc4bceb629bcdd068559f4f57802a69904ed
Closes-Bug: 1712654